Propeller.



No. 838,313. PATBNTED DEC. 11, 1906,

-PROPELLBR.

APPLIOATIDN FILED 1113.16, 1906.

JOSE FoLA, 'or vALENcrA, SPAIN.

PROPELLER.

Specification of Letters Patent.

Patented Dec. 11, 1906.

Application filed February 16, 1906. Serial No. 301,448.

T0 @ZZ whom, t may concern:

Be it'known that I, JOS FOLA, (whose mothers name is Igurbide,) a subject of the King of Spain, residing at Valencia, in the Province of Valencia, Spain, have invented new and useful Improvements in Propellers, of which the following is a specication.

This invention relates to propellers 'which may be used in marine propulsion, aerial navigation, hydraulic installations, either for raising water or being driven by water, or in steam-driven plants, and in fact for any purpose to which propellers of this type are applicable.

The invention consists, essentially, in a particular form of propeller in which the blades have a helicoidal curvature, and this curvature is determinedin the following manner: If a sphere be taken and caused to revolve simultaneously relatively to two of its diameters at right angles to one another while its center remains stationary, a radius of the sphere will describe in space an area or surface of helicoidal outline, and it is this surface which will constitute a blade of the propeller made according to this invention. Helicoidal curves of various angles or pitches may be described by selecting the radius in various positions relative to the pairs of diameters. The angle or pitch of the helicoidal chosen will depend entirely upon the use which is to be made of the propeller. The propeller may be made to any required size and with any desired number of blades as may be considered desirable for the purpose to which it is tobe applied.

In the accompanying drawings, Figure l shows in end elevation a double or biconcentric propeller made in accordance with this invention, and Fig. 2 shows a side elevation of the same propeller.

Four blades a, c, and d, each of helicoidal shape, as above defined, are mounted on the principal or inner shaft, while four narrow blades or strips A, B, C, and D of inverse curvature to the blades a, I), c, and (Z are arranged concentrically with the inner propeller with their ends on sleeves or the like embracing the inner shaft, so that the two parts of the propeller-7l. e., the inner blades a, b, c, and d and outer blades A, B, C, and D-can be caused to rotate in opposite directions. rPhe outer set of blades may be geared to the shaft of the inner set in any convenient way, if required, so that-both sets of blades can be driven from or can impart power to the one shaft while they rotate in opposite directions.

The blades may be of any convenient material-such as steel, iron, bronze, copper, or other metals, vwoods of various kinds, sailcloth, silk, and other textile materials. The material chosen will depend upon the purpose for which the propeller is intended and the fluid in which it is to work.

That I claim is- 1. A propeller the blades of which are of helicoidal curvature such that their surfaces can be described by the radius of a sphere when said sphere is caused to rotate simultaneously relatively to two of its diameters, the edge of the blade lying on the surface of the sphere, and the blade being attached to the shaft along a diametral line.

2. A propeller having two sets of helicoidal blades arranged concentrically, the outer set being of inverse curvature to the inner set, each of said sets of blades being attached to its shaft along a diametral line and having an edge lying on the surface of a sphere.

3. A propeller comprising two sets of helicoidal blades adapted to rotate in opposite directions, the one set of blades being of inverse curvature to the other set, each set being attached to its shaft along a diametral line and having an edge lying on the surface of a sphere.

In testimony whereof I have signed my name to this speciiieation in the presence of two subscribing witnesses. j

JOSE FOLA.

Vitnesses:

PABLO F. BARRAOHINA, SALVADOR MORAGUES. 

